Cartridge accommodation case

ABSTRACT

A cartridge accommodation case includes a generally rectangular cartridge accommodation top case formed with partitioned rooms for holding plural cartridges and a generally rectangular cartridge accommodation bottom case having partitioned rooms which have substantially the same shape as and opposed to the partitioned rooms of the top case. The top case and the bottom case have the same structure and are provided with projections and recesses which can engage each other. The cartridge accommodation case is given, inside, partitioned rooms which are two times larger in space than the partitioned rooms of the top case and the bottom case when the top case and the bottom case are placed one on the other and the projections and the recesses are engaged with each other. The top case and the bottom case are provided with ribs which are fitted into/with each other when cartridge accommodation cases are stacked.

FIELD OF THE INVENTION

The present invention relates to a cartridge accommodation case (accommodation box) for accommodating flat-body-shaped cartridges each of which incorporates a magnetic tape reel. More particularly, the invention relates to a cartridge accommodation case which enables stable stacking of cartridge accommodation cases.

BACKGROUND OF THE INVENTION

Conventionally, to pack one-reel-type magnetic recording tape cartridges together, as shown in FIG. 8, one cartridge 1 is housed in each case 3 and plural cases 3 are packed in a corrugated cardboard box 5. Necessary buffering performance is thus attained.

However, in this accumulated packing, since cartridges 1 are accommodated in a corrugated cardboard box 5, to check the presence/absence, types, etc. of cartridges 1 it is necessary to open the corrugated cardboard box 5, which is low in convenience.

Another problem is that in the event of flooding a corrugated cardboard box 5 which is packed with cartridges 1 becomes wet and may be broken.

As an exemplary countermeasure against the above problems, Non-patent document (LTO-Ultrium L-pack, [online], TDK Corp., Internet <URL:http://www.tdk.com/professional/lto/ltolpack.html>) discloses a plastic case 7 shown in FIG. 9 which is transparent (the contents are seen through it) and is not reduced in case strength even if water sticks to it. The case 7 has come to be marketed.

However, in the case 7 disclosed in the above-mentioned Non-patent document, accommodation spaces 9 for housing individual cartridges 1 are defined by plural partitioning projections 11 and one cartridge 1 is stored in each accommodation space 9. That is, the cartridges 1 are accommodated discretely. Therefore, in actual housing work, cartridges 1 are put into the case 7 one by one, which is inconvenient particularly in the case where a large number of cartridges 1 need to be stored.

Furthermore, in the above case 7, since the accommodation spaces 9 are defined individually, the whole accommodation area (i.e., the top opening area of the case 7) is divided into equal areas corresponding to the respective accommodation spaces 9. Therefore, the weight of almost all accommodated cartridges 1 is concentrated on end case portions 13 and 15. This raises a problem that the case 7 is low in the resistance to impact and hence in the ability to absorb impact when the case 7 is dropped.

Still further, when cases 7 are stacked in the vertical direction, they are rendered unstable because they are not formed with proper ribs.

SUMMARY OF THE INVENTION

The present invention has been made in view of the above circumstances, and an object of the invention is therefore to provide a cartridge accommodation case capable of realizing high efficiency of housing work and high stackability (stacked cases are stable and do not collapse) while securing sufficient resistance to impact.

To attain the above object, the invention provides a cartridge accommodation case which is composed of a generally rectangular cartridge accommodation top case formed with partitioned rooms for holding respective cartridge groups in each of which plural flat-body-shaped cartridges each incorporating a magnetic tape reel are arranged side by side in a thickness direction thereof so as to assume a block form and a generally rectangular cartridge accommodation bottom case having partitioned rooms which have substantially the same shape as and opposed to the partitioned rooms of the top case, the top case and the bottom case having the same structure and provided with projections and recesses which can engage each other, cartridge accommodation case being given, inside, partitioned rooms which are two times larger in space than the partitioned rooms of the top case and the bottom case when the top case and the bottom case are placed one on the other and the projections and the recesses are engaged with each other, characterized in that the top case and the bottom case are provided with ribs which are fitted into/with each other when cartridge accommodation cases are stacked.

A first preferable embodiment of the invention is characterized in that, in the cartridge accommodation case according to the invention, the top case and the bottom case can be separated from each other.

A second preferable embodiment of the invention is characterized in that, in the cartridge accommodation case according to the first preferable embodiment, the ribs provided in the top case and the ribs provided in the bottom case are in a fitting relationship of a convex portion and a concave portion.

A third preferable embodiment of the invention is characterized in that, in the cartridge accommodation case according to the second preferable embodiment of the invention, the ribs provided in the top case and the ribs provided in the bottom case are different from each other in shape.

A fourth preferable embodiment of the invention is characterized in that, in the cartridge accommodation case according to the second or third preferable embodiment, the convex portions which are to contact inside surfaces of the concave portions are solid projections.

In the cartridge accommodation case of the invention, the top case and the bottom case are provided with the ribs which are fitted into/with each other when cartridge accommodation cases are stacked. Since cartridge accommodation cases can be stacked by fitting them into/with each other, they do not collapse even in the event of not a small earthquake or vibration.

In the cartridge accommodation case of the first preferable embodiment of the invention, the top case and the bottomcase can be separated from each other. Therefore, things can be housed or taken out freely during work by removing the top case.

In the cartridge accommodation case of the second preferable embodiment of the invention, the ribs provided in the top case and the ribs provided in the bottom case are in a fitting relationship of a convex portion and a concave portion. Therefore, the ribs can easily be fitted into/with each other and are not easily disengaged from each other.

In the cartridge accommodation case of the third preferable embodiment of the invention, the ribs provided in the top case and the ribs provided in the bottom case are different from each other in shape. Therefore, free spaces are formed and fitting is made reliably even in a dusty environment.

In the cartridge accommodation case of the fourth preferable embodiment of the invention, the convex portions which are to contact the inside surfaces of the concave portions are solid projections. Therefore, strong convex portions are obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a cartridge accommodation case according to the invention being separated into a top case and a bottom case.

FIGS. 2A and 2B are a plan view and a side view, respectively, of the bottom case shown in FIG. 1.

FIGS. 3A and 3C show the cartridge accommodation case in which FIG. 3A is a side view as viewed from the direction indicated by arrow A in FIG. 2A and FIG. 3B shows an appearance of an important part of the cartridge accommodation case, more specifically, buffer ribs formed in the outer wall of a partitioned room.

FIGS. 4A, 4B, 4C and 4D show a procedure of housing plural cartridges in the cartridge accommodation case.

FIGS. 5A and 5B show how a cartridge accommodation case is put on another cartridge accommodation case in a stable manner in which FIG. 5A is a front view of a single cartridge accommodation case and FIG. 5B is a front view of two cartridge accommodation cases which are stacked in the vertical direction.

FIGS. 6A and 6B illustrate arrangements of rectangular frames which are different from the ones shown in FIGS. 5A and 5B, in which FIG. 6A is a top view of the top case and FIG. 6B is a bottom view of the bottom case.

FIGS. 7A and 7B illustrate various combinations of a convex portion and a concave portion that are different from each other in shape.

FIG. 8 is an explanatory diagram showing conventional method 1 for accommodating plural cartridges.

FIG. 9 is an explanatory diagram showing conventional method 2 for accommodating plural cartridges.

DETAILED DESCRIPTION OF THE INVENTION

A cartridge accommodation case according to a preferred embodiment of the present invention will be hereinafter described in detail with reference to FIGS. 1 to 7.

FIG. 1 is an exploded perspective view of the cartridge accommodation case to which the invention is directed in a state that it separated into a top case and a bottom case. FIGS. 2A and 2B are a plan view and a side view, respectively, of the bottom case shown in FIG. 1. FIGS. 3A and 3B shows the cartridge accommodation case in which FIG. 3A is a side view as viewed from the direction indicated by arrow A in FIG. 2A and FIG. 3B shows an appearance of an important part of the cartridge accommodation case, more specifically, buffer ribs formed in the outer wall of a partitioned room.

For example, the cartridge accommodation case 100 can be used suitably for housing flat-body-shaped cartridges 21 each of which incorporates a magnetic tape reel.

Each cartridge 21 incorporates the magnetic tape reel (not shown) in such a manner that its axial direction coincides with the thickness direction of the cartridge. Although the embodiment is directed to an exemplary case that each cartridge 21 is a square flat body, each cartridge may have other shapes such as a rectangular flat body shape.

The cartridge accommodation case 100 can be opened and closed because a top case 23 and a bottom case 25 having the same structure are placed one on the other and engaged with each other. Plural partitioned rooms 27 are formed inside by engaging the top case 23 and the bottom case 25 with each other. In this embodiment, four partitioned rooms 27 are formed. As shown in FIG. 1, each partitioned room 27 can hold a cartridge group 29 in which plural cartridges 21 are arranged side by side in their thickness direction so as to assume a block form. As shown in FIG. 1, cartridges 21 are oriented in such a manner that their tape access mouths, which are low is strength, are located sideways so as to be adjacent to the center lines of the cartridge accommodation case 100. It is even preferable that the tape access mouths of a cartridge group 29 accommodated in one partitioned room 27 be opposed to the tape access mouths of a cartridge group 29 accommodated in another partitioned room 33. In this case, the tape access mouths are located adjacent to the one center line of the cartridge accommodation case 100 and can be protected from impact coming from outside the cartridge accommodation case 100.

In this embodiment, the accommodation capacity of each partitioned room 27 is approximately equal to the volume of a cartridge group 29 consisting of five cartridges 21. Therefore, even if cartridges 21 are put carelessly into the partitioned rooms 27, the cartridges 21 can be set in place easily because each partitioned room 27 has no internal partition walls. For example, one can grip two or three cartridges 21 together and put them into a partitioned room 27, which makes the efficiency of housing work much higher than in conventional cases with which it is necessary to grip and insert cartridges one by one.

Since plural cartridges 27 are accommodated together in block form, a wider surplus area that does not contribute to accommodation can be secured than in a case that plural cartridges 21 are accommodated discretely in the same accommodation area. In the cartridge accommodation case 100, the surplus area portions are used as impact absorbing portions (what is called “crushable zones”).

More specifically, flanges 31 as impact absorbing portions extend at both ends, in the axial direction of the magnetic tape reels 25, of each of the top case 23 and the bottom case 25. A handle hole 33 of a handle to be used in carrying the cartridge accommodation case 100 is formed in each flange 31. That is, one can carry the cartridge accommodation case 100 formed by engaging the top case 23 and the bottom case 25 with each other by inserting a hand into the handle holes 33 of one opposed pair of flanges 31 (the other opposed pair of flanges 31 is located down). It is also possible to carry the cartridge accommodation case 100 in the horizontal direction by inserting both hands into the handle holes 33 of both opposed pairs of flanges 31.

Assume a case that as described above a person is carrying the cartridge accommodation case 100 by gripping the handle of one flange 31 with one hand with the other flange 31 located down. If the cartridge accommodation case 100 slips off hie or her hand, the lower flange 31 of the cartridge accommodation case 100 hits a floor surface. At this time, the flange 31 as an impact absorbing portion is deformed by the weight of the cartridge accommodation case 100 and the cartridge groups 29. The impact energy is absorbed by the deformation and impact on the accommodated cartridges 21 is thus reduced.

In general, cartridges are vulnerable to impact that is exerted in the reel axial direction, for the following reason. There may occur a case that a portion of a wound magnetic tape projects from its side surface. If a tape edge of the projected portion of the magnetic tape hits a reel flange, the projected portion may be crushed, bent, or deformed otherwise to obstruct smooth rewinding and paying-out of the magnetic tape. In the worst case, reading and writing are disabled. In this embodiment, since the flanges 31 as impact absorbing portions are provided at both ends in the reel axial direction of the accommodated cartridges 21, the resistance to impact in the reel axial direction (the cartridges 27 themselves are vulnerable to impact in this direction) is increased.

FIG. 3B shows an appearance of an important part of the cartridge accommodation case, more specifically, buffer ribs formed in the outer wall of a partitioned room.

The wall surface of each partitioned room 27 is formed with buffer ribs 35 which extends outward from the partitioned room 27. Therefore, even if an external object collides with the cartridge accommodation case 100, by virtue of the buffer ribs 35 gaps are formed between the case outer wall and the cartridges 21. The buffer ribs 35 serve as cushion members and the resistance to impact is thereby increased. In particular, as shown in FIG. 3B, a buffer rib 37 is formed at the corner of each partitioned room 27 so as to surround an edge of a cartridge 21. An impact absorbing function is thus provided which effectively prevents deformation of the cartridge edges when, for example, the cartridge accommodation case 100 is dropped in a state that cartridges 21 are accommodated therein.

The cartridge accommodation case 100 is composed of the top case 23 and the bottom case 25 which have the same structure and have projections (projection strips) 41 and recesses (grooves) 43 that can engage each other. In this embodiment, as shown in FIG. 2A, the projection strip 41 (above) and the groove 43 (below) are formed symmetrically with respect to the case center line 45 so as to surround the four partitioned rooms 27. That is, in each of the top case 23 and the bottom case 25, the projection strip 41 is formed continuously in a bracket shape on one side of the case center line 45 and the groove 43 is formed continuously in a bracket shape on the other side of the case center line 45.

When the top case 23 and the bottom case 25 having the same structure are placed one on the other and combined together, the projection strips 41 go into and engage the grooves 43. As a result, the partitioned rooms 27 are closed so tightly as to attain waterproofness and the cartridge accommodation case 100 can even float on the water. Furthermore, the cartridges 21 can be protected from dust, moisture, splashed water, and other harmful substances. The same case can be used as either of a lid and a body. Therefore, in the cartridge accommodation case 100, the partitioned rooms 27 are formed by the two cases of one kind (formed by using a single metal die) so as to be able to be opened and closed by means of the projection strips 41 and the grooves 43.

Partitions 47 are provided between the partitioned rooms 27. The partitions 47 are formed in such shapes and with such heights (described later) as to be deformed easily by impact. That is, when the cartridge accommodation case 100 is dropped, the partitions 47 are deformed and the impact is thereby reduced. The partitions extend in both of the direction in which the flanges 31 are arranged and the direction perpendicular to it so as to accommodate either of a case that the cartridge accommodation case 100 is dropped with the arrangement direction of the flanges 31 coincident with the vertical direction and a case that it is dropped with the arrangement direction of the flanges 31 coincident with the horizontal direction. In this embodiment, the partitions 47 are formed in cross form so as to provide the four partitioned rooms 27.

In the cartridge accommodation case 100, since the partitions 47 exist between the partitioned rooms 27 for accommodating cartridge groups 29, even when impact is exerted on the individual cartridge groups 29 due to a drop, for example, the partitions 47 absorb the impact and the impact force due to the inertia of each cartridge group 29 is prevented from affecting the other cartridge groups 29.

Incidentally, the cartridge accommodation case 100 accommodating cartridge groups 29 are housed in a corrugated cardboard box (not shown) whose inside shape is approximately the same as the outside shape of the cartridge accommodation case 100. Therefore, to allow the cartridge accommodation case 100 to be taken out of the corrugated cardboard box easily, each flange 31 has, on both sides, chamfered portions 49 each having an inclined sideline (about 45°). As a result, triangular holes corresponding to the chamfered portions 49 are formed between the cartridge accommodation case 100 accommodated in the corrugated cardboard box and the inside wall surface of the corrugated cardboard box, which allows the cartridge accommodation case 100 to be taken out easily by inserting hands or fingers into these holes.

Although not shown in any drawings, a picking piece may be provided so as to extend from each chamfered portion 49. In this case, in a state that the top case 23 and the bottom case 25 are placed one on the other in the vertical direction so as to form the partitioned rooms 27, the top case 23 and the bottom case 25 can easily be disengaged from each other by separating two associated picking pieces from each other in the vertical direction.

A bent portion is formed at the outer periphery of each of the top case 23 and the bottom case 25 by bending a narrow peripheral portion. Like each of the projection strip 41 and the groove 43, the bent portion is provided on one side of the center line 45. As a result, when the top case 23 and the bottom case 25 are placed one on the other, the bent portion of the top case 23 or the bottom case 25 covers the peripheral portion of the other, which increases the dustproofness and the waterproofness.

Large rectangular frames 53 a and small rectangular frames 53 b which can be loosely fitted into the frames 53 a expand outward from the bottom walls of the partitioned rooms 27. Even if cartridge accommodation cases 100 are stacked in the vertical direction, the bottom rectangular frames 53 a and 53 b of an upper cartridge accommodation case 100 are fitted with or into the top rectangular frames 53 b and 53 a of a lower cartridge accommodation case 100, whereby relative horizontal deviation is restricted and the stacked cartridge accommodation cases 100 are prevented from collapsing. This will be described later in detail.

Each of the top case 23 and the bottom case 25 is an integral formed body of a plastic resin. Therefore, the top case 23 and the bottom case 25 which are strong enough to protect the cartridges 21 reliably and have a proper impact absorbing ability can be mass-produced easily at a low cost by using a material that can be handled relatively easily.

For example, the plastic resin may contain polyethylene terephthalate, polypropylene, or polystyrene, in which case the material can be acquired easily, waste cartridge accommodation cases 100 can be collected and reused, and vacuum forming can be performed easily at a low cost.

It is preferable that the plastic resin be transparent. In this case, even in a state that the top case 23 and the bottom case 25 are engaged with each other to close the partitioned rooms 33 tightly, the cartridges 21 accommodated in the partitioned rooms 27 can be seen from the outside. Therefore, one can easily recognize how the cartridges 21 are accommodated in the partitioned rooms 27 which are closed tightly.

Since the top case 23 and the bottom case 25 are formed by drawing a plastic resin sheet of 0.5 to 2.0 mm in thickness, minimum necessary structure-dependent strength of the partitioned rooms 27 for accommodating plural cartridge groups 29 can be secured economically and the weight of the entire cartridge accommodation case 100 can be minimized while its minimum necessary strength is satisfied. Since the top case 23 and the bottom case 25 are formed by working on a sheet whose thickness is in the above-mentioned range, a proper degree of deformation can be caused in the cartridge accommodation case 100 when external force is applied to it. Optimum impact absorbing action for the accommodated cartridges 21 can be realized. That is, if a sheet used is unduly thin, deformation is caused too easily and the impact absorbing effect is lowered. On the other hand, a sheet used is unduly thick, deformation is not caused easily and impact is transmitted directly to the cartridges 21. The configuration of the embodiment enables formation of optimum impact absorbing portions (crushable zones) by setting the thickness of a plastic resin sheet in the above-mentioned range.

FIGS. 4A, 4B, 4C and 4D shows a procedure of housing plural cartridges in the above-described cartridge accommodation case.

In FIG. 4A, reference symbol C1 denotes a first cartridge group to be housed in a single partitioned room 27 of the cartridge accommodation case 100 and symbol C2 denotes a second cartridge group to be housed in another single partitioned room 27 of the cartridge accommodation case 100.

FIG. 4B shows a state that the first cartridge group C1 and the second cartridge group C2 are accommodated in the bottom case 25.

As shown in FIG. 4C, the top case 23 is then put on the bottom case 25.

FIG. 4D shows a state that the top case 23 and the bottom case 25 are combined together. It is seen through the transparent cartridge accommodation case 100 that the first cartridge group C1 and the second cartridge group C2 are accommodated in the different partitioned rooms 27.

FIGS. 5A and 5B shows how the cartridge accommodation case according to the invention obtained by placing the top case on the bottom case and combining them together as shown in FIG. 4D is put on another cartridge accommodation case in a stable manner, in which FIG. 5A is a front view of a single cartridge accommodation case and FIG. 5B is a front view of two cartridge accommodation cases which are stacked in the vertical direction.

As shown in FIG. 5A, in the cartridge accommodation case 100 obtained by placing the top case 23 on the bottom case 25 and combining them together, large projected rectangular frames 100-Concave (53 a in FIG. 1) each of which forms a rectangular recess inside expand outward from the bottom wall of the bottom case 25 at right and left positions in the figure. Although not appearing in FIG. 5A, small projected rectangular frames 100-Convex (53 b in FIG. 1) each of which forms a rectangular recess inside expand outward from the bottom wall of the bottom case 25 at right and left positions (behind the rectangular frames 100-Concave) in the figure. The rectangular frames 100-Convex and 100-Concave have such dimensions that the rectangular frame 100-Convex can fit into the rectangular recess that is formed inside the rectangular frame 100-Concave.

On the other hand, small projected rectangular frames 100-Convex (53 b in FIG. 1) each of which forms a rectangular recess inside expand outward from the top wall of the top case 23 at right and left positions in FIG. 5A. Although not appearing in FIG. 5A, large projected rectangular frames 100-Concave (53 a in FIG. 1) each of which forms a rectangular recess inside expand outward from the top wall of the top case 23 at right and left positions (behind the rectangular frames 100-Convex) in the figure. The rectangular frames 100-Convex and 100-Concave have such dimensions that the rectangular frame 100-Convex can fit into the rectangular recess that is formed inside the rectangular frame 100-Concave.

When a cartridge accommodation case 100-2 obtained by placing the top case 23 on the bottom case 25 and combining them together is put on another cartridge accommodation case 100-1 as shown in FIG. 5B, the small rectangular frames 100-Convex (53 b in FIG. 1) formed in the top wall of the cartridge accommodation case 100-1 are fitted into the rectangular recesses that are formed inside the large rectangular frames 100-Convex (53 a in FIG. 1) formed in the bottom wall of the cartridge accommodation case 100-2, whereby the cartridge accommodation cases 100-1 and 100-2 are combined together. The thus-stacked cartridge accommodation cases 100-1 and 100-2 do not collapse even if they receive non-small vibration.

FIGS. 6A and 6B illustrate rectangular frames which are different from the rectangular frames 100-Convex and 100-Concave shown in FIGS. 5A and 5B, in which FIG. 6A is a top view of the top case and FIG. 6B is a bottom view of the bottom case (or vice versa). Hatched portions in FIGS. 6A and 6B are projections.

Reference symbol 53 a 1 in FIG. 6A denotes rectangular frames that are integral with the top case 23, and reference symbol 53 a 2 in FIG. 6B denotes rectangular frames that are integral with the bottom case 25. The projection defined by the outside surface of the rectangular frame 53 a 1 and the recess defined by the inside surface of the rectangular frame 53 a 2 have such dimensions that the former fits into the latter. To enable fitting, it is desirable that the outside dimension of the projection and the inside dimension of the recess be as close to each other as possible (larger than 0 mm and smaller than or equal to 1 mm).

In a state that the cartridge accommodation case 100 is formed by placing the top case 23 of FIG. 6A on the bottom case 25 of FIG. 6B and combining them together as shown in FIG. 4D, the large projected rectangular frames 53 a 2 each of which forms a rectangular recess inside expand outward from the bottom wall of the bottom case 25 at the positions corresponding to the four corners. On the other hand, the small projected rectangular frames 53 a 1 each of which forms a rectangular recess inside expand outward from the top wall of the top case 23 at the positions corresponding to the four corners.

When a cartridge accommodation case 100-2 obtained by placing the top case 23 on the bottom case 25 and combining them together is put on another cartridge accommodation case 100-1 as shown in FIG. 5B, the small rectangular frames 53 a 1 formed in the top wall of the cartridge accommodation case 100-1 are fitted into the rectangular recesses that are formed inside the large rectangular frames 53 a 2 formed in the bottom wall of the cartridge accommodation case 100-2, whereby the cartridge accommodation cases 100-1 and 100-2 are combined together. The thus-stacked cartridge accommodation cases 100-1 and 100-2 do not collapse even if they receive non-small vibration.

There are a variety of combinations of small convex portions and large concave portions. Hatched portions in FIGS. 6A and 6B are projections. In the example of FIGS. 6A and 6B, the four small rectangular frames (convex portions) 53 al are provided in the top case 23 and the four large rectangular frames (concave portions) 53 a 2 are provided in the bottom case 25. This arrangement is suitable for a case that accommodated things should not be turned over.

As shown in FIG. 1, each of the top case 23 and the bottom case 25 may be provided with a pair of small rectangular frames 53 a and a pair of large rectangular frames 53 b in such a manner that the two pairs are disposed side by side. This arrangement is suitable for a case that accommodated things should not be oriented reversely in the right-left direction.

Furthermore, each of the top case 23 and the bottom case 25 may be provided with a pair of small rectangular frames 53 a and a pair of large rectangular frames 53 b in such a manner that each pair occupies diagonal positions. This arrangement is suitable for a case that it is allowable for accommodated things to be turned over and oriented reversely in the right-left direction.

The example of FIGS. 6A and 6B is such that the small rectangular frame 53 a 1 and the large rectangular frame 53 a 2, which are the same in shape, are provided as a small convex portion and a large concave portion. However, the invention is not limited to such a case and a small convex portion and a large concave portion may be provided that are different from each other in shape. FIGS. 7A and 7B illustrate various combinations of a small convex portion and a large concave portion.

FIG. 7A shows an example in which an inner rib 53 b 2 fits in an outer rib 53 b 1. The rib shape may be square or triangular. Hatched portions in FIG. 7A are projections.

Part (1) shows an example in which a circular inner rib 53 b 2 fits in a square outer rib 53 b 1. Part (2) shows an example in which a circular inner rib 53 c 2 fits in a triangular outer rib 53 c 1. These exemplary combinations are different from the combination of FIGS. 6A and 6B (contact is made in the entire circumference) in that the circular inner rib 53 b 2 or 53 c 2 is in contact with the outer rib 53 b 1 or 53 c 1 merely at four or three points and the other portions of the ribs are free. These exemplary combinations are suitable for use in a dusty environment because the fitting is not impaired even if not a small amount of dust or the like is accumulated in the free spaces. In addition, these examples are superior in design.

FIG. 7B shows examples in which inner ribs 53 d 2, 53 e 2, and 53 f 2 are solid projections. More specifically, part (1) shows an example in which a circular projection 53 d 2 fits in a square outer rib 53 d 1. Part (2) shows an example in which a circular projection 53 e 2 fits in a triangular outer rib 53 e 1. Part (3) shows an example in which a square projection 53 f 2 fits in a square outer rib 53 f 1. Since the inner ribs 53 d 2, 53 e 2, and 53 f 2 are solid projections, the examples of FIG. 7B are strong though a larger amount of material is necessary. As such, these examples are effective for a case that high strength is required. In addition, these examples are superior in design.

As described above, the invention can provide a cartridge accommodation case capable of realizing high efficiency of housing work and high stackability (stacked cases are stable) while securing high resistance to impact.

This application is based on Japanese Patent application JP 2006-23066, filed Jan. 31, 2006, the entire content of which is hereby incorporated by reference, the same as if set forth at length. 

1. A cartridge accommodation case comprising: a generally rectangular cartridge accommodation top case formed with partitioned rooms for holding respective cartridge groups in each of which plural flat-body-shaped cartridges each incorporating a magnetic tape reel are arranged side by side in a thickness direction thereof so as to assume a block form; and a generally rectangular cartridge accommodation bottom case having partitioned rooms which have substantially the same shape as and opposed to the partitioned rooms of the top case, the top case and the bottom case having the same structure and provided with projections and recesses which can engage each other, the cartridge accommodation case being given, inside, partitioned rooms which are two times larger in space than the partitioned rooms of the top case and the bottom case when the top case and the bottom case are placed one on the other and the projections and the recesses are engaged with each other, wherein the top case and the bottom case are provided with ribs which are fitted into/with each other when cartridge accommodation cases are stacked.
 2. The cartridge accommodation case according to claim 1, wherein the top case and the bottom case are capable of being separated from each other.
 3. The cartridge accommodation case according to claim 2, wherein the ribs provided in the top case and the ribs provided in the bottom case are in a fitting relationship of a convex portion and a concave portion.
 4. The cartridge accommodation case according to claim 3, wherein the ribs provided in the top case and the ribs provided in the bottom case are different from each other in shape.
 5. The cartridge accommodation case according to claim 3, wherein the convex portions which are to contact inside surfaces of the concave portions are solid projections.
 6. The cartridge accommodation case according to claim 4, wherein the convex portions which are to contact inside surfaces of the concave portions are solid projections. 